1. Field of the Invention
Embodiments of the present invention relate to image encoding and/or decoding, and more particularly, to a system, medium, and method efficiently encoding and/or decoding a sensor image.
2. Description of the Related Art
In general, mobile devices, such as digital cameras, use one charge-coupled device (CCD) plate as an image capture device. When an image input through one CCD plate is encoded and decoded, first, a color component that is absent in relation to each pixel is obtained through interpolation and then, color transform from an RGB image into a YUV image is performed. At this time, in addition to the occurrence of redundant data in the interpolation process, a rounding error can occur in the color transform process. In order to reduce the redundant data and improve the compression ratio, there has been an attempt to implement a processing of a 4:2:0 format YUV image that is generated by sampling the chromaticity components (U, V) of a YUV image into a ¼ size. However, in this case, the characteristic of an image provided from a sensor, such as a CCD plate, cannot be reflected correctly, resulting in the picture quality of a restored image being degraded.
Meanwhile, in order to enable encoding and/or decoding of a high quality picture by reducing the rounding error occurring in the color transform process, an RGB image may be directly processed without the color transform process. However, in this case, only a 4:4:4 format RGB image is processed, compared to the above 4:2:0 format YUV image, which results in the bit rate increasing and the amount of data to be processed increasing relatively. As a result, complexity increases due to increases in the capacity and bandwidth of memory, resulting in such a directly processing of the RGB image without the color transform process not being suitable for mobile devices.
Leading examples of the conventional technologies applied to image encoding and decoding as described above include ISO/IEC MPEG-4 video encoding international standard (“Text of ISO/IEC FDIS 14496-2: Information Technology—Generic coding of audio-visual objects—Part 2: Visual) and H.264/MPEG-4 pt.10 AVC standardization technology (“Text of ISO/IEC FDIS 14496-10: Information Technology—Coding of audio-visual objects—Part 10: Advanced Video Coding”, ISO/IEC JTC 1/SC 29/WG 11, N5555, March, 2003) of Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG.